2. Brazing

WARNING

•R-134a itself is not flammable at atmospheric pressure and temperatures up to

212°F (100°C).

•R-134a itself is not explosive or poisonous. However, when exposed to high temperatures (open flames), R-134a can be decomposed to form hydrofluoric acid and carbonyl fluoride both of which are hazardous.

•Do not use silver alloy or copper alloy containing arsenic.

•Use an electronic leak detector or soap bubbles to check for leaks. Add a trace of refrigerant to the system (if using an electronic leak detector), and then raise the pressure using nitrogen gas (140 PSIG). Do not use R-134a as a mixture with pressurized air for leak testing.

1)Braze all fittings while purging with nitrogen gas flowing at a pressure of 3 to 4 PSIG.

NOTICE

•Always install a new drier every time the sealed refrigeration system is opened.

Do not replace the drier until after all other repair or replacement has been made. Install the new drier with the arrow on the drier in the direction of the refrigerant flow.

•When brazing, protect the drier by using a wet cloth to prevent the drier from overheating. Do not allow the drier to exceed 250°F (121°C).

2)Use an electronic leak detector or soap bubbles to check for leaks. Add a trace

of refrigerant to the system (if using an electronic leak detector), and then raise the pressure using nitrogen gas (140 PSIG). Do not use R-134a as a mixture with pressurized air for leak testing.

3.Evacuation and Recharge (R-134a)

1)Attach a vacuum pump to the system. Be sure the high-side charging hose is connected to the field-installed high-side access valve.

IMPORTANT

The vacuum level and vacuum pump may be the same as those for current refrigerants. However, the rubber hose and gauge manifold to be used for evacuation and refrigerant charge should be exclusively for POE oils.

2)Turn on the vacuum pump, then open the high-side valve on the gauge manifold. Never allow the oil in the vacuum pump to flow backwards.

3)Allow the vacuum pump to pull down to a 29.9" Hg vacuum. Evacuating period depends on pump capacity.

4)Close the high-side valve on the gauge manifold.

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Hoshizaki HR24A service manual Brazing, Evacuation and Recharge R-134a
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HR24A specifications

The Hoshizaki HR24A is an advanced refrigeration unit designed to meet the cooling needs of commercial kitchens and food storage facilities. Known for its reliability and efficiency, this model showcases several innovative features that set it apart in the competitive market of commercial refrigeration.

One of the standout characteristics of the Hoshizaki HR24A is its robust construction. Built with a durable stainless steel exterior, it not only adds aesthetic appeal but also ensures longevity and resistance to corrosion and wear. The interior is designed for easy cleaning, with rounded corners that minimize the buildup of grime and food particles.

The HR24A offers an impressive storage capacity, making it ideal for establishments with high-volume food storage requirements. With a temperature range typically between 33°F and 38°F, the unit maintains optimal conditions for preserving perishables such as meats, dairy, and vegetables. This precision in temperature control is essential for maintaining food safety and quality.

One of the key technologies integrated into the Hoshizaki HR24A is its advanced refrigeration system. Utilizing a highly efficient compressor and a fan-assisted cooling feature, the unit ensures rapid temperature recovery even in busy kitchen environments. This is crucial during peak hours when door openings are frequent, as it helps maintain consistent internal temperatures.

Energy efficiency is another hallmark of the HR24A. It is designed with environmentally friendly refrigerants and complies with Energy Star standards, which can lead to significant cost savings over time through reduced electricity consumption. This commitment to environmental responsibility makes it an attractive option for eco-conscious businesses.

In terms of user-friendliness, the HR24A is equipped with digital controls and adjustable shelving, allowing for customized organization according to specific storage needs. The LED lighting inside the unit provides excellent visibility, making it easy to locate items quickly, which is particularly beneficial during busy service periods.

Overall, the Hoshizaki HR24A combines durability, efficiency, and functionality, making it an exceptional choice for anyone seeking a reliable refrigeration solution in a commercial kitchen setting. Whether used in restaurants, hotels, or catering businesses, its impressive features and state-of-the-art technology continue to meet the demanding requirements of the foodservice industry.
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